Abstract

Ultraviolet curable coatings for protecting optical fibers are widely used throughout the world. These coatings enable fiber manufacturers to produce high-performance optical fibers at rapid line speed with easy handling. One important property of these coatings, critical to optimum fiber performance, is the cured film’s viscoelastic behavior. However, no method has been available to measure viscoelastic cured film properties directly on optical fibers. Viscoelastic values measured on free films are presumed to be representative of the cured film behavior on coated optical fiber. This paper describes a new instrument for measuring the viscoelastic properties of cured UV curable coatings directly on optical fiber. Conventional torsional pendulum analysis has been reported to be a suitable technique for this purpose.¹ However, accurate viscoelastic properties, such as shear modulus, loss modulus, and dissipation factor.² have not been measured by this method. The shortcoming of the conventional torsional pendulum method is the difficulty in canceling the fiber's effect on the measurement of the coating.

© 1987 Optical Society of America